TextEditingTool: Identify the TextBlock (and node)

I need to verify that the input that the user inserted is correct. The user can insert data in several nodes (some nodes have several textblocks to user insert data too). I thought to use TextEditingTool to do this but how can i identify each textblock from each node using TextEditingTool? Thanks for your support

Sorry I have found the solution looking for your API reference. I must use the property "this.TextBlock.Name "

public class CustomTextEditingTool : TextEditingTool
protected override bool IsValidText(string oldstring, string newstring)
switch (this.TextBlock.Name)

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